JPWO2017082232A1 - Base station, user equipment, reference signal transmission method and signal reception method - Google Patents

Abstract

  A base station that communicates with a user apparatus in a radio communication system that supports LTE, a section represented by a predetermined subframe in which a synchronization signal is mapped in a time direction, and a section in which the synchronization signal is mapped in a frequency direction And generating a signal to which the UE-specific reference signal is mapped according to a first pattern in which the UE-specific reference signal is mapped to resource elements other than the resource element to which the synchronization signal is mapped. A base station is provided that includes a generation unit and a transmission unit that transmits the generated signal.

Description

  The present invention relates to a base station, a user apparatus, a reference signal transmission method, and a signal reception method.

  In the LTE (Long Term Evolution) system, a plurality of reference signals (Reference Signals) used for user equipment (UE: User Equipment) to perform downlink (DL) channel estimation, reception quality measurement, and the like are defined. ing. For example, CRS (Cell Specific Reference Signal), CSI-RS (Channel State Information Reference Signal), UE-RS (UE Specific Reference Signal), etc. are defined. ing.

  In the LTE system, the SS (Synchronization Signal) used for the user apparatus to perform time and frequency synchronization with a base station (eNB: enhanced NodeB) is a PSS (Primary Synchronization Signal) and SSS. (Secondary Synchronization Signal) is defined (see Non-Patent Document 1).

  In the LTE system, a plurality of transmission modes (TM) are defined as downlink transmission schemes. For example, TM9 is a transmission mode added in 3GPP Rel-10, and supports 8-layer MIMO using a maximum of 8 antenna ports.

3GPP TS36.211 V12.7.0 (2015-09) 3GPP TS36.213 V12.7.0 (2015-09)

  In a part of downlink transmission modes (for example, TM9, TM10, etc.), the user apparatus receives PDSCH (Physical Downlink Shared Channel) using UE-RS.

  Here, according to Non-Patent Document 2, in the transmission mode, in the subframe to which the SS is mapped (included), the user apparatus is the PDSCH RB (resource block) allocated to itself in the subframe. When an RB to which an SS is mapped is included in part, it is specified that the subframe operates so as not to receive all RBs of the PDSCH allocated to itself.

  Since this rule exists, the base station needs to perform PDSCH scheduling so as to avoid the RB to which the SS is mapped in the subframe to which the SS is mapped. Therefore, the base station cannot use up all RBs, which causes a decrease in throughput (including a decrease in peak throughput) and a decrease in radio capacity. For example, when UL / DL subframe configuration (UL / DL subframe configuration) = 2 in TDD (Time division Duplex), a throughput decrease of about 6% occurs.

  A specific example will be described with reference to the drawings. For example, as shown in FIG. 1A, all RBs of the PDSCH of the entire system band are allocated to the same user apparatus, and SS (SSS in the example of FIG. 1A) is included in some RBs of the RBs. Assume that it was. In the case of FIG. 1A, the user apparatus operates so as not to receive all RBs of the PDSCH of the entire system band.

  Therefore, as shown in FIG. 1B, the base station performs scheduling so as to avoid the RB to which the SS is mapped in the subframe to which the SS is mapped. PDSCH scheduling in the frequency direction is performed in units of RB groups (1 RB group = 4 RBs when the bandwidth is 20 MHz). In addition, PDSCH scheduling in the time direction is performed in units of two RBs (hereinafter referred to as “RB pairs”) in one subframe. Since the SS is mapped to a band of about 6 RBs at the center of the bandwidth, in the example of FIG. 1B, the base station can cover the range of 3 RB groups (3 × 4 = 12 RBs) at the center of the bandwidth within one subframe. It is necessary to schedule PDSCH so as to avoid RB pairs.

  Here, when the RB to which the SS is mapped is included in a part of the RB of the PDSCH allocated to the user apparatus, the user apparatus does not receive all the RBs of the PDSCH allocated to the user apparatus. The reason why the operation is specified will be briefly described with reference to the drawings. As shown in FIG. 2, on the PDSCH, a plurality of reference signals are scattered and mapped throughout the PDSCH. The range of A indicates an RB pair to which SS is not mapped, and the range of B indicates an RB pair to which SS is mapped. As shown in FIG. 2, in the range of B, SS is mapped to a part of resource elements to which UE-RS is originally mapped. In other words, a part of UE-RS is missing. If a part of the UE-RS is missing, the user apparatus cannot correctly receive the UE-RS, and as a result, cannot correctly demodulate the RB. For this reason, the above-mentioned regulations are provided.

  The disclosed technique has been made in view of the above, and an object of the present invention is to provide a technique capable of improving throughput in a wireless communication system supporting LTE.

  A base station of the disclosed technology is a base station that communicates with a user apparatus in a radio communication system supporting LTE, and includes a section represented by a predetermined subframe to which a synchronization signal is mapped in a time direction, A UE-specific reference signal according to a first pattern in which a UE-specific reference signal is mapped to a resource element other than a resource element to which the synchronization signal is mapped in a range surrounded by a section to which the synchronization signal is mapped. Includes a generation unit that generates a signal to be mapped, and a transmission unit that transmits the generated signal.

  According to the disclosed technology, a technology capable of improving throughput in a wireless communication system supporting LTE is provided.

It is a figure for demonstrating a subject. It is a figure for demonstrating a subject. It is a figure for demonstrating a subject. It is a figure which shows the mapping of UE-RS (UE-specific RS) prescribed | regulated by 3GPP. It is a figure which shows UL / DL subframe configuration of TDD. It is a figure which shows configuration of Special subframe. It is a figure which shows the position where PSS / SSS is mapped. It is a figure which shows the position where PSS / SSS is mapped. It is a figure which shows the system configuration example of the radio | wireless communications system which concerns on embodiment. It is a sequence diagram which shows the process sequence of the radio | wireless communications system which concerns on embodiment. It is a figure for demonstrating the process procedure 1 which concerns on embodiment. It is a figure for demonstrating the process procedure 1 which concerns on embodiment. It is a figure for demonstrating the process sequence 2-1 which concerns on embodiment. It is a figure for demonstrating the process sequence 2-1 which concerns on embodiment. It is a figure for demonstrating the process sequence 2-2 which concerns on embodiment. It is a figure for demonstrating the process sequence 2-2 which concerns on embodiment. It is a figure for demonstrating the process sequence 2-3 which concerns on embodiment. It is a figure for demonstrating the process sequence 2-3 which concerns on embodiment. It is a sequence diagram which shows the process sequence of the radio | wireless communications system which concerns on embodiment. It is a figure which shows the function structural example of the base station which concerns on embodiment. It is a figure which shows the function structural example of the user apparatus which concerns on embodiment. It is a figure which shows the hardware structural example of the base station which concerns on embodiment. It is a figure which shows the hardware structural example of the user apparatus which concerns on embodiment.

  Embodiments of the present invention will be described below with reference to the drawings. The embodiment described below is only an example, and the embodiment to which the present invention is applied is not limited to the following embodiment. For example, although the wireless communication system according to the present embodiment assumes a system based on LTE, the present invention is not limited to LTE and can be applied to other systems. In addition, in this specification and claims, “LTE” corresponds to not only a communication method corresponding to Release 8 or 9 of 3GPP but also Release 10, 11, 12, 13, or Release 14 or later of 3GPP. It is used in a broad sense including the fifth generation communication system.

<Locations where UE-RS and SS are mapped>
First, the position where UE-RS prescribed | regulated by the present 3GPP is mapped is demonstrated. According to Non-Patent Document 2, UE-RS performs frequency multiplexing (FDM: Frequency Division Multiplex) and code division multiplexing (CDM: Code Division Multiplex) for each antenna port as shown in FIG. It is mapped to the element and transmitted from the base station eNB.

  FIG. 3 shows, in order from the left, the pattern of resource elements to which UE-RSs transmitted in antenna port 7, antenna port 8, antenna port 9, and antenna port 10 are mapped. In each pattern, the UE-RS is transmitted after being CDMed using two consecutive resource elements in the time direction. In other words, if one of the two consecutive resource elements is missing, the user apparatus UE cannot correctly receive the UE-RS.

  In addition, FIG. 3 shows “3, 4, 8, or 9” in the case of special subframes in which the TDD special subframe configuration is “1, 2, 6, or 7” in order from the top. In the case of a special subframe that is “other (including a TDD downlink subframe and FDD)”, the resource element pattern to which the UE-RS is mapped is shown. In the following description, each pattern in which UE-RS is mapped as shown in FIG. 3 is referred to as “conventional UE-RS mapping pattern” for convenience.

  Here, a TDD special subframe configuration will be briefly described. A special subframe is a special subframe provided in order to avoid interference between DL and UL when switching from DL to UL in TDD. As shown in FIG. 4, the special subframe is provided at a predetermined position for each UL / DL subframe configuration. As shown in FIG. 5, the special subframe further defines nine types of special subframes with different DL / GP (Guard Period) / UL ratios.

  Next, the SS defined in the current 3GPP will be described. FIG. 6A shows a position where PSS / SSS is mapped in FDD-LTE. As shown in FIG. 6A, in FDD-LTE, the PSS is mapped to the last OFDM symbol in slots 0 and 10. The SSS is mapped to the OFDM symbol adjacent to the left of the PSS.

  FIG. 6B shows a position where PSS / SSS is mapped in TDD-LTE. As shown in FIG. 6B, in TDD-LTE, PSS is mapped to the third OFDM symbol of subframes 1 and 6. The SSS is mapped to the last OFDM symbol of subframes 0 and 5.

<System configuration and operation overview>
FIG. 7 is a diagram illustrating a system configuration example of the wireless communication system according to the embodiment. As illustrated in FIG. 7, the radio communication system according to the embodiment includes a base station eNB and a user apparatus UE. In the example of FIG. 7, one base station eNB and one user apparatus UE are illustrated, but a plurality of base stations eNB may be included, or a plurality of user apparatuses UE may be included. Good.

  FIG. 8 is a sequence diagram illustrating a processing procedure of the wireless communication system according to the embodiment. The base station eNB assigns the PDSCH RB to the user apparatus UE, maps the UE-RS to the assigned RB in a predetermined pattern, and includes the DL data in the PDSCH in the assigned RB to the user apparatus UE. Send.

  The user apparatus UE recognizes the RB of the PDSCH assigned thereto by DCI (Downlink Control Information) included in the PDCCH (Physical Downlink Control Channel). When DL data is transmitted in a transmission mode in which the user apparatus UE needs to receive the PDSCH using the UE-RS, the user apparatus UE receives the UE-RS mapped in the RB assigned to the user apparatus UE, and receives the received UE. -PDSCH channel estimation is performed using RS. The user apparatus UE demodulates the PDSCH using the channel estimation value and receives (acquires) DL data.

  Here, in the conventional LTE, as described above, in the transmission mode in which the user apparatus UE receives the PDSCH using the UE-RS, the user apparatus UE is allocated to itself in the subframe to which the SS is mapped. When an RB to which an SS is mapped is included in a part of an RB of a PDSCH that is present, it is specified that the mobile terminal does not receive all the RBs of the PDSCH allocated to itself. Also, the base station eNB needs to perform PDSCH scheduling so as to avoid the RB to which the SS is mapped in the subframe to which the SS is mapped.

  On the other hand, in the present embodiment, by using the processing procedure described below, the base station eNB schedules PDSCH without avoiding the RB to which the SS is mapped, even in the subframe to which the SS is mapped. Works to do. Further, the user apparatus UE is also allocated to itself even if the RB to which SS is mapped is included in the RB of PDSCH allocated to itself in the subframe to which SS is mapped. It operates to receive the PDSCH RB.

<Processing procedure>
(Processing procedure 1)
In the processing procedure 1, “conventional UE-RS mapping pattern” is applied as it is as the position of the resource element to which the UE-RS is mapped.

  When the RB to which the SS is mapped is included in the RB of the PDSCH allocated to the user apparatus UE in the subframe to which the SS is mapped, only the UE-RS that does not overlap with the SS is used. It operates to receive the RB of the PDSCH assigned to itself. Also, the base station eNB operates to perform PDSCH scheduling without avoiding the RB to which the SS is mapped even in the subframe to which the SS is mapped.

  FIG. 9A and FIG. 9B are diagrams for explaining the first processing procedure according to the embodiment. The squares in FIGS. 9A and 9B correspond to resource elements. 9A and 9B, the positions where UE-RSs are mapped are “other (including TDD downlink subframe and FDD)” in “conventional UE-RS mapping patterns” shown in FIG. Corresponds to the pattern of resource elements to which UE-RS is mapped. 9A and 9B corresponds to SSS in TDD (as described in FIG. 6B, SSS in TDD is mapped to the last symbol of the subframe). The same applies to FIGS. 10 to 12 described below.

  A specific example of a processing procedure performed by the user apparatus UE and the base station eNB will be described with reference to FIGS. 9A and 9B. In the section in which the SS is mapped in the frequency direction, the user apparatus UE is UE-RS mapped to the area A in FIGS. 9A and 9B (that is, UE-RS mapped to two consecutive resource elements). ) To receive the PDSCH RB assigned to itself.

  On the other hand, as illustrated in FIGS. 9A and 9B, the base station eNB operates to perform PDSCH scheduling without avoiding the RB to which the SS is mapped even in the subframe to which the SS is mapped. As shown in FIG. 9A, the base station eNB may transmit a UE-RS that lacks a part in the area B, or a part lacks in the area B as shown in FIG. 9B. PDSCH may be transmitted instead of UE-RS.

  As described above, according to the first processing procedure, the base station eNB can perform PDSCH scheduling without avoiding the RB to which the SS is mapped even in the subframe to which the SS is mapped. Further, the user apparatus UE can receive the RB to which the SS is mapped even in the subframe to which the SS is mapped. Thereby, it is possible to improve throughput in the wireless communication system.

(Processing procedure 2)
In the process procedure 2, in the subframe to which the SS is mapped, the position of the resource element to which the UE-RS is mapped is shifted to a position different from the “conventional UE-RS mapping pattern”, so that the SS and Resource elements to which UE-RS is mapped are prevented from overlapping (collision).

  In the following description, the pattern in which the position of the UE-RS is shifted so that the resource elements to which the SS and the UE-RS are mapped does not overlap (collision) is referred to as “new UE-RS mapping pattern”. Call it.

  The user apparatus UE operates to receive the RB of the PDSCH allocated to the user apparatus UE using the UE-RS transmitted in the “new UE-RS mapping pattern” in the subframe to which the SS is mapped. To do.

  The base station eNB transmits the UE-RS according to the “new UE-RS mapping pattern” in the subframe to which the SS is mapped, and performs PDSCH scheduling without avoiding the RB to which the SS is mapped. To work. Hereinafter, process procedure 2 will be described by dividing it into a plurality of process procedures.

(Processing procedure 2-1)
10A and 10B are diagrams for explaining the processing procedure 2-1 according to the embodiment. FIG. 10A shows the position of UE-RS in a subframe in which SS is transmitted, and FIG. 10B shows the position of UE-RS in a subframe in which SS is not transmitted.

  As shown in FIG. 10A, the base station eNB is within the range surrounded by the section represented by the subframe in which the SS is mapped in the time direction and the section in which the SS is mapped in the frequency direction. The UE-RSs that overlap (collision) with the SS among the UE-RSs mapped in are shifted in the time direction so as not to collide with the SS (shift to the UE-RS position shown in A of FIG. 10A, It operates so as to transmit the UE-RS in accordance with the “new UE-RS mapping pattern” shifted back by 3 resource elements in the time direction.

  In addition, in the subframe in which the SS is transmitted, the base station eNB does not transmit a section in which the overlap (collision) between the SS and the UE-RS does not occur in the frequency direction (section in which the SS is not mapped in the frequency direction). In the subframe, UE-RS is transmitted according to “conventional UE-RS mapping pattern”. Specifically, the base station eNB transmits the UE-RS for the region B in FIG. 10A and the region A in FIG. 10B without shifting the position of the UE-RS.

  In the subframe in which the SS is transmitted, the user apparatus UE transmits the UE-RS transmitted in the “new UE-RS mapping pattern” and the UE-RS transmitted in the “conventional UE-RS mapping pattern”. Are used to perform channel estimation and receive the PDSCH RB assigned to itself. Further, the user apparatus UE performs channel estimation using the UE-RS transmitted in the “conventional UE-RS mapping pattern” in the subframe in which the SS is not transmitted, and determines the RB of the PDSCH allocated to itself. Operates to receive.

  The position of the UE-RS shown in FIG. 10A and FIG. 10B is mapped to the UE-RS in the case of “others (including TDD downlink subframe and FDD)” in the pattern shown in FIG. 3 as described above. This corresponds to the resource element pattern, and the SS position corresponds to the SSS in TDD.

  As described with reference to FIG. 6A, in the case of FDD, PSS is mapped to the SS position in FIG. 10A, and SSS is mapped to the adjacent symbol. Therefore, even in the case of FDD, collision of SS and UE-RS can be avoided by using the “new UE-RS mapping pattern” shown in FIGS. 10A and 10B.

[Variation of “New UE-RS Mapping Pattern”]
The “new UE-RS mapping pattern” shown in FIG. 10A and FIG. 10B is an example. In this embodiment, if the SS and the UE-RS do not collide, the UE-RS is assigned to the resource element at any position. It is possible to shift to For example, in this processing procedure, as a “new UE-RS mapping pattern”, a pattern in which the UE-RS at the position shown in A of FIG. 10A is further shifted back by one resource element in the time direction is used. May be.

  Further, the position of the UE-RS may be shifted in the frequency direction in addition to the time direction. For example, as the “new UE-RS mapping pattern”, the UE-RS shown in A of FIG. 10A is further shifted by 1 to 4 resource elements in the frequency direction (for example, the right or left direction of FIG. 10A). A pattern may be used.

  Also, as shown in FIG. 3, in the case of a special subframe whose TDD special subframe configuration is “1, 2, 6 or 7”, the special which is “3, 4, 8 or 9”. In the case of a subframe, the resource element pattern to which the UE-RS is mapped is different from the case of “others (including TDD downlink subframe and FDD)”. Therefore, for TDD special subframes to which these special subframe configurations are applied, a pattern different from the patterns described so far may be applied as the “new UE-RS mapping pattern”. Good.

  Also, different patterns may be applied to TDD and FDD as “new UE-RS mapping pattern”.

  In addition, in a subframe in which CSI-RS exists, “conventional UE-RS mapping pattern” may be applied without applying “new UE-RS mapping pattern”.

(Processing procedure 2-2)
In the process procedure 2-2, the “new UE-RS mapping pattern” is applied in the subframe in which the SS is transmitted, and “conventional UE-RS in the subframe in which the SS is not transmitted”. "Mapping pattern" is applied. Other points that are not mentioned may be the same as the procedure 2-1.

  11A and 11B are diagrams for explaining the processing procedure 2-2 according to the embodiment. FIG. 11A shows the position of UE-RS in a subframe in which SS is transmitted, and FIG. 11B shows the position of UE-RS in a subframe in which SS is not transmitted. As shown in FIG. 11A, the base station eNB shifts the UE-RS to the position shown in A of FIG. 11A according to the “new UE-RS mapping pattern” in the subframe in which the SS is transmitted. UE-RS is transmitted. Moreover, as shown to FIG. 11B, the base station eNB transmits UE-RS according to the "conventional UE-RS mapping pattern" in the sub-frame where SS is not transmitted.

  When receiving the RB of the PDSCH in the subframe in which the SS is transmitted, the user apparatus UE performs channel estimation using the UE-RS transmitted in the “new UE-RS mapping pattern” and is allocated to itself. It operates to receive the RB of the current PDSCH. Further, the user apparatus UE performs channel estimation using the UE-RS transmitted in the “conventional UE-RS mapping pattern” in the subframe in which the SS is not transmitted, and the RB of the PDSCH allocated to itself. Works to receive.

(Processing procedure 2-3)
In the processing procedure 2-3, the “new UE-RS mapping pattern” is applied to all the subframes. Other points that are not mentioned may be the same as the procedure 2-1.

  12A and 12B are diagrams for explaining the processing procedure 2-3 according to the embodiment. FIG. 12A shows the position of the UE-RS in the subframe in which the SS is transmitted, and FIG. 12B shows the position of the UE-RS in the subframe in which the SS is not transmitted. As shown in FIGS. 12A and 12B, the base station eNB shifts the UE-RS to the position shown in A of FIG. 12A and A of FIG. -Send RS.

  When receiving the PDSCH RB, the user apparatus UE performs channel estimation using the UE-RS transmitted in the “new UE-RS mapping pattern”, and receives the PDSCH RB allocated to itself. To work.

  As described above, according to the processing procedure No. 2, the base station eNB can perform PDSCH scheduling without avoiding the RB to which the SS is mapped even in the subframe to which the SS is mapped. Further, the user apparatus UE can receive the RB to which the SS is mapped even in the subframe to which the SS is mapped. Thereby, it is possible to improve throughput in the wireless communication system.

(Supplementary items for each processing procedure)
The user apparatus UE and the base station eNB in the embodiment support only one of the processing procedure 1, the processing procedure 2-1, the processing procedure 2-2, and the processing procedure 2-3 described above. Alternatively, some or all of these processing procedures may be supported, and the processing procedure to be used may be instructed from the base station eNB to the user apparatus UE.

  Further, the user apparatus UE may notify the base station eNB that it has the capability to cope with the processing procedure described above.

  FIG. 13 is a sequence diagram illustrating a processing procedure of the wireless communication system according to the embodiment. The user apparatus UE transmits a capability notification message indicating that the user apparatus UE has the capability corresponding to the processing procedure described above to the base station eNB (S21). In addition, the user apparatus UE specifically specifies the processing procedure that it corresponds to among the processing procedure 1, the processing procedure 2-1, the processing procedure 2-2, and the processing procedure 2-3. You may make it notify to eNB. The capability notification message may be a UECapabilityInformation message in the RRC message.

  Then, base station eNB transmits the message which instruct | indicates transmitting UE-RS to the user apparatus UE using the process sequence which concerns on this Embodiment (S22). In step S22, the base station eNB may transmit a message specifically instructing which processing procedure to use to the user apparatus UE. The message may be, for example, an RRC message or a MAC layer control message.

  Subsequently, the base station eNB transmits DL data using the processing procedure instructed to the user apparatus UE (S23).

<Functional configuration>
(base station)
FIG. 14 is a diagram illustrating a functional configuration example of the base station according to the embodiment. As illustrated in FIG. 14, the base station eNB includes a signal transmission unit 101, a signal reception unit 102, a capability management unit 103, and a transmission signal generation unit 104. FIG. 14 shows only functional units that are particularly related to the embodiment of the present invention in the base station eNB, and has at least a function (not shown) for performing an operation based on LTE. The functional configuration shown in FIG. 14 is only an example. As long as the operation according to the present embodiment can be executed, the function classification and the name of the function unit may be anything. However, a part of the processing of the base station eNB described so far (for example, only one specific processing procedure or a plurality of specific processing procedures) may be executable.

  The signal transmission unit 101 includes a function of generating a radio signal from the signal generated by the transmission signal generation unit 104 and wirelessly transmitting the signal. The signal receiving unit 102 includes a function of wirelessly receiving various signals from each user apparatus UE and acquiring a higher layer signal from the received physical layer signal.

  It is assumed that each of the signal transmission unit 101 and the signal reception unit 102 includes a packet buffer and performs layer 1 (PHY), layer 2 (MAC, RLC, PDCP), and layer 3 (RRC) processing (however, But not limited to this).

  The capability management unit 103 has a function of acquiring a capability notification message from the user apparatus UE and storing it in a memory or the like. Moreover, the capability management part 103 notifies the transmission signal production | generation part 104 that the user apparatus UE respond | corresponds to the process procedure which concerns on this Embodiment. In addition, the capability management unit 103 may notify the user apparatus UE that the UE-specific reference signal is transmitted using the “new UE-RS mapping pattern”.

  The transmission signal generation unit 104 generates various signals in the lower layer from the signals in the upper layer to be transmitted from the user apparatus UE, and outputs the signals in which the generated various signals are mapped to predetermined resources (resource elements). Generate and pass to the signal transmission unit 101. The signal transmission unit 101 may include a transmission signal generation unit 104. The signal generated by the transmission signal generation unit 104 includes various reference signals (UE-RS, CRS, CSI-RS, etc.), a synchronization signal (PSS / SSS), a signal related to PDSCH, and a signal related to PDCCH. Further, when mapping the UE-RS to a predetermined resource, the transmission signal generation unit 104 sets the UE-RS according to the pattern of either “conventional UE-RS mapping pattern” or “new UE-RS mapping pattern”. RS is mapped to a predetermined resource.

(User device)
FIG. 15 is a diagram illustrating a functional configuration example of the user apparatus according to the embodiment. As illustrated in FIG. 15, the user apparatus UE includes a signal transmission unit 201, a signal reception unit 202, a capability notification unit 203, and a reference signal management unit 204. FIG. 15 shows only functional units particularly related to the embodiment of the present invention in the user apparatus UE, and has at least a function (not shown) for performing an operation based on LTE. The functional configuration shown in FIG. 15 is only an example. As long as the operation according to the present embodiment can be executed, the function classification and the name of the function unit may be anything. However, a part of the processing of the user apparatus UE described so far (for example, only one specific processing procedure or a plurality of processing procedures) may be executable.

  The signal transmission unit 201 has a function of generating and wirelessly transmitting various signals to be transmitted from the user apparatus UE. The signal receiving unit 202 has a function of receiving various radio signals from the base station eNB. Each of the signal transmission unit 201 and the signal reception unit 202 includes a packet buffer, and is assumed to perform layer 1 (PHY), layer 2 (MAC, RLC, PDCP), and layer 3 (RRC) processing (however, But not limited to this).

  In addition, the signal reception unit 202 includes a resource element pattern (“conventional UE-RS mapping pattern” or “new UE-RS mapping pattern” to which the UE-RS managed by the reference signal management unit 204 is mapped. )), The UE has the function of recognizing the position of the resource element to which the UE-RS is transmitted and receiving the UE-RS. In addition, the signal reception unit 202 receives (acquires) DL data by performing channel estimation using the received UE-RS and further performing PDSCH demodulation using the channel estimation value. The signal receiving unit 202 may be divided into a first receiving unit that receives a reference signal and a second receiving unit that performs demodulation of PDSCH and the like.

  The capability notification unit 203 transmits a capability notification message indicating that the user apparatus UE itself supports the processing procedure according to the present embodiment to the base station eNB.

  The reference signal management unit 204 has a function of managing a resource element pattern (“conventional UE-RS mapping pattern” or “new UE-RS mapping pattern”) to which the UE-RS is mapped. In addition, the reference signal management unit 204 may manage in which pattern the UE-RS is mapped in accordance with an instruction from the base station eNB.

  The functional configurations of the user apparatus UE and the base station eNB described above may be realized entirely with hardware circuits (for example, one or a plurality of IC chips), or may be partially configured with hardware circuits. This part may be realized by a CPU and a program.

(base station)
FIG. 16 is a diagram illustrating a hardware configuration example of the base station according to the embodiment. FIG. 16 shows a configuration closer to the mounting example than FIG. As illustrated in FIG. 16, the base station eNB performs processing such as an RE (Radio Equipment) module 301 that performs processing related to a radio signal, a BB (Base Band) processing module 302 that performs baseband signal processing, and a higher layer. It has a device control module 303 and a communication IF 304 which is an interface for connecting to a network.

  The RE module 301 should transmit the digital baseband signal received from the BB processing module 302 from the antenna by performing D / A (Digital-to-Analog) conversion, modulation, frequency conversion, power amplification, and the like. Generate a radio signal. In addition, a digital baseband signal is generated by performing frequency conversion, A / D (Analog to Digital) conversion, demodulation, and the like on the received radio signal, and the digital baseband signal is passed to the BB processing module 302. The RE module 301 includes, for example, part of the signal transmission unit 101 and the signal reception unit 102 illustrated in FIG.

  The BB processing module 302 performs processing for mutually converting an IP packet and a digital baseband signal. A DSP (Digital Signal Processor) 312 is a processor that performs signal processing in the BB processing module 302. The memory 322 is used as a work area for the DSP 312. The BB processing module 302 includes, for example, a part of the signal transmission unit 101, a part of the signal reception unit 102, and the transmission signal generation unit 104 illustrated in FIG.

  The device control module 303 performs IP layer protocol processing, OAM (Operation and Maintenance) processing, and the like. The processor 313 is a processor that performs processing performed by the device control module 303. The memory 323 is used as a work area for the processor 313. The auxiliary storage device 333 is, for example, an HDD or the like, and stores various setting information for operating the base station eNB itself. The device control module 303 includes, for example, the capability management unit 103 shown in FIG.

(User device)
FIG. 17 is a diagram illustrating a hardware configuration example of the user apparatus according to the embodiment. FIG. 17 shows a configuration closer to the mounting example than FIG. As illustrated in FIG. 17, the user apparatus UE includes an RE module 401 that performs processing related to a radio signal, a BB processing module 402 that performs baseband signal processing, a device control module 403 that performs processing such as an upper layer, and a SIM card. And a SIM slot 404 that is an interface for accessing the.

  The RE module 401 generates a radio signal to be transmitted from the antenna by performing D / A conversion, modulation, frequency conversion, power amplification, and the like on the digital baseband signal received from the BB processing module 402. In addition, a digital baseband signal is generated by performing frequency conversion, A / D conversion, demodulation, and the like on the received radio signal, and passed to the BB processing module 402. The RE module 401 includes, for example, part of the signal transmission unit 201 and the signal reception unit 202 illustrated in FIG.

  The BB processing module 402 performs processing for mutually converting an IP packet and a digital baseband signal. The DSP 412 is a processor that performs signal processing in the BB processing module 402. The memory 422 is used as a work area for the DSP 412. The BB processing module 402 includes, for example, a part of the signal transmission unit 201, a part of the signal reception unit 202, and a reference signal management unit 204 shown in FIG.

  The device control module 403 performs IP layer protocol processing, various application processing, and the like. The processor 413 is a processor that performs processing performed by the device control module 403. The memory 423 is used as a work area for the processor 413. The processor 413 reads / writes data from / to the SIM via the SIM slot 404. The device control module 403 includes, for example, a capability notification unit 203 illustrated in FIG.

<Summary>
As described above, according to the embodiment, a base station that communicates with a user apparatus in a radio communication system that supports LTE, a section represented by a predetermined subframe to which a synchronization signal is mapped in a time direction, and a frequency direction UE-specific reference according to a first pattern in which a UE-specific reference signal is mapped to a resource element other than a resource element to which the synchronization signal is mapped in a range surrounded by a section to which the synchronization signal is mapped A generator for generating a signal to which the signal is mapped;
There is provided a base station having a transmitter for transmitting the generated signal. The base station eNB provides a technique capable of realizing an improvement in throughput in a radio communication system supporting LTE.

  Further, the generation unit includes the first pattern in a resource element in a range surrounded by a section represented by the predetermined subframe in the time direction and a section in which the synchronization signal is not mapped in the frequency direction. A signal to which the UE-specific reference signal is mapped with a different second pattern may be generated. Thereby, base station eNB can transmit UE-RS, applying "conventional UE-RS mapping pattern" about RB where SS is not mapped.

  In addition, the generation unit may perform UE in the first pattern on resource elements in a range surrounded by a section represented by the predetermined subframe in the time direction and a section in which the synchronization signal is not mapped in the frequency direction. A signal to which the unique reference signal is mapped may be generated. Accordingly, the base station eNB can transmit the UE-RS by uniformly applying a “new UE-RS mapping pattern” in the subframe to which the SS is mapped, which can simplify the processing procedure. it can.

  The generation unit may generate a signal in which a UE-specific reference signal is mapped in the first pattern to a resource element in a subframe to which a synchronization signal is not mapped in the time direction. Accordingly, the base station eNB can transmit the UE-RS by applying a uniform “new UE-RS mapping pattern” in all subframes, and can further simplify the processing procedure.

  In addition, when the channel state information reference signal is mapped to a section represented by the predetermined subframe in the time direction, the generation unit assigns resource elements in the section represented by the predetermined subframe in the time direction. A signal to which the UE-specific reference signal is mapped in a second pattern different from the first pattern may be generated. Accordingly, the base station eNB can transmit the UE-RS by applying the “conventional UE-RS mapping pattern” in the subframe to which the CSI-RS is mapped, thereby simplifying the processing procedure. be able to.

  Moreover, you may further have the management part which notifies that the said UE apparatus transmits the UE specific reference signal mapped by said 1st pattern. Thereby, the base station eNB can notify the user apparatus UE in advance that the processing procedure according to the present embodiment is applied.

  Further, according to the embodiment, a base station that communicates with a user apparatus in a radio communication system that supports LTE, a section represented by a predetermined subframe to which a synchronization signal is mapped in a time direction, and a frequency direction Among resource elements in which UE-specific reference signals are mapped in a predetermined pattern to resource elements in a range surrounded by a section to which the synchronization signal is mapped, and UE-specific reference signals are mapped according to the predetermined pattern, A generation unit that generates a signal in which a physical downlink shared channel signal is mapped instead of a UE-specific reference signal to a resource element that is continuous in a time direction with a symbol to which the synchronization signal is mapped in the range; And a transmitter that transmits the signal. The base station eNB provides a technique capable of realizing an improvement in throughput in a radio communication system supporting LTE.

  In addition, according to the embodiment, a user apparatus that communicates with a base station in a radio communication system supporting LTE, a section represented by a predetermined subframe to which a synchronization signal is mapped in a time direction, and a frequency direction Receiving UE-specific reference signals that are mapped to resource elements that are continuous in the time direction among UE-specific reference signals that are mapped in a predetermined pattern to resource elements in a range surrounded by a section to which the synchronization signal is mapped There is provided a user apparatus having a first receiving unit that receives a signal of a physical downlink shared channel using the UE-specific reference signal received by the first receiving unit. . This user apparatus UE provides a technique capable of improving throughput in a radio communication system supporting LTE.

  Further, according to the embodiment, there is provided a reference signal transmission method executed by a base station that communicates with a user apparatus in a radio communication system supporting LTE, and is represented by a predetermined subframe to which a synchronization signal is mapped in the time direction. A UE-specific reference signal is mapped to a resource element other than a resource element to which the synchronization signal is mapped in a range surrounded by a section to which the synchronization signal is mapped in the frequency direction A reference signal transmission method is provided that includes generating a signal to which a UE-specific reference signal is mapped according to the pattern, and transmitting the generated signal. With this reference signal transmission method, a technique capable of improving throughput in a wireless communication system supporting LTE is provided.

  In addition, as described above, according to the embodiment, a signal reception method executed by a user apparatus communicating with a base station in a radio communication system supporting LTE, in a predetermined subframe to which a synchronization signal is mapped in a time direction Among UE-specific reference signals mapped in a predetermined pattern to resource elements in a range surrounded by a section represented by the section to which the synchronization signal is mapped in the frequency direction, mapping is performed on resource elements continuous in the time direction A signal reception method comprising: receiving a UE-specific reference signal to be received; and receiving a physical downlink shared channel signal using the received UE-specific reference signal. With this signal reception method, a technique capable of improving throughput in a wireless communication system supporting LTE is provided.

<Supplement of embodiment>
As described above, the configuration of each device (user device UE / base station eNB) described in the embodiment of the present invention is realized by executing the program by the CPU (processor) in the device including the CPU and the memory. It may be a configuration, may be a configuration realized by hardware such as a hardware circuit provided with processing logic described in the present embodiment, or may be a mixture of programs and hardware Good.

  Although the embodiments of the present invention have been described above, the disclosed invention is not limited to such embodiments, and those skilled in the art will understand various variations, modifications, alternatives, substitutions, and the like. I will. Although specific numerical examples have been described in order to facilitate understanding of the invention, these numerical values are merely examples and any appropriate values may be used unless otherwise specified. The classification of items in the above description is not essential to the present invention, and the items described in two or more items may be used in combination as necessary. It may be applied to the matters described in (if not inconsistent). The boundaries between functional units or processing units in the functional block diagram do not necessarily correspond to physical component boundaries. The operations of a plurality of functional units may be physically performed by one component, or the operations of one functional unit may be physically performed by a plurality of components. The order of the sequences and flowcharts described in the embodiments may be changed as long as there is no contradiction. For convenience of processing description, the user apparatus UE / base station eNB has been described using a functional block diagram, but such an apparatus may be realized by hardware, software, or a combination thereof. The software operated by the processor of the user apparatus UE according to the embodiment of the present invention and the software operated by the processor of the base station eNB according to the embodiment of the present invention are random access memory (RAM), flash memory, and read-only, respectively. The data may be stored in a memory (ROM), EPROM, EEPROM, register, hard disk (HDD), removable disk, CD-ROM, database, server, or any other suitable storage medium.

  In the embodiment, the “new UE-RS mapping pattern” is an example of a first pattern. The “conventional UE-RS mapping pattern” is an example of a second pattern and a predetermined pattern.

  This patent application claims priority based on Japanese Patent Application No. 2015-220792 filed on November 10, 2015, the entire contents of Japanese Patent Application No. 2015-220792 are incorporated herein by reference. To do.

UE user apparatus eNB base station 101 signal transmission unit 102 signal reception unit 103 capability management unit 104 transmission signal generation unit 201 signal transmission unit 202 signal reception unit 203 capability notification unit 204 reference signal management unit 301 RE module 302 BB processing module 303 device control Module 304 Communication IF
401 RE module 402 BB processing module 403 Device control module 404 SIM slot

Claims (10)

A base station that communicates with a user apparatus in a wireless communication system supporting LTE,
A resource element to which the synchronization signal is mapped in a range surrounded by a section represented by a predetermined subframe to which the synchronization signal is mapped in the time direction and a section to which the synchronization signal is mapped in the frequency direction A generator that generates a signal to which a UE-specific reference signal is mapped according to a first pattern in which a UE-specific reference signal is mapped to a resource element other than
A transmitter for transmitting the generated signal;
Base station with The generator is
In a resource element in a range surrounded by a section represented by the predetermined subframe in the time direction and a section in which the synchronization signal is not mapped in the frequency direction, the UE has a second pattern different from the first pattern. Generate a signal to which the unique reference signal is mapped,
The base station according to claim 1. The generator is
The UE-specific reference signal is mapped in the first pattern to resource elements in a range surrounded by a section represented by the predetermined subframe in the time direction and a section in which the synchronization signal is not mapped in the frequency direction. Generate signal,
The base station according to claim 1. The generator is
Generating a signal in which a UE-specific reference signal is mapped in the first pattern to a resource element in a subframe to which a synchronization signal is not mapped in the time direction;
The base station according to claim 3. The generator is
When a channel state information reference signal is mapped to a section represented by the predetermined subframe in the time direction, the resource pattern in the section represented by the predetermined subframe in the time direction is assigned to the first pattern and Generate a signal to which the UE-specific reference signal is mapped in a different second pattern,
The base station as described in any one of Claims 1 thru | or 4. A management unit that notifies the user apparatus to transmit a UE-specific reference signal mapped in the first pattern;
The base station according to claim 1, comprising: A base station that communicates with a user apparatus in a wireless communication system supporting LTE,
UE-specific reference signals in a predetermined pattern in resource elements in a range surrounded by a section represented by a predetermined subframe to which a synchronization signal is mapped in the time direction and a section to which the synchronization signal is mapped in the frequency direction Is mapped,
Among resource elements to which a UE-specific reference signal is mapped according to the predetermined pattern, a resource element that is continuous in a time direction with a symbol to which the synchronization signal is mapped in the range is replaced with a physical downlink instead of a UE-specific reference signal. A generator for generating a signal to which a signal of the shared channel is mapped;
A transmitter for transmitting the generated signal;
Base station with A user apparatus that communicates with a base station in a wireless communication system supporting LTE,
UE-specific mapping to a resource element in a range surrounded by a section represented by a predetermined subframe to which a synchronization signal is mapped in the time direction and a section to which the synchronization signal is mapped in the frequency direction A first receiving unit that receives a UE-specific reference signal mapped to resource elements that are continuous in the time direction among the reference signals;
A second receiving unit that receives a physical downlink shared channel signal using the UE-specific reference signal received by the first receiving unit;
A user device. A reference signal transmission method executed by a base station communicating with a user apparatus in a wireless communication system supporting LTE,
A resource element to which the synchronization signal is mapped in a range surrounded by a section represented by a predetermined subframe to which the synchronization signal is mapped in the time direction and a section to which the synchronization signal is mapped in the frequency direction Generating a signal to which the UE-specific reference signal is mapped according to a first pattern in which the UE-specific reference signal is mapped to a resource element other than:
Transmitting the generated signal;
A reference signal transmission method comprising: A signal reception method executed by a user apparatus communicating with a base station in a wireless communication system supporting LTE,
UE-specific mapping to a resource element in a range surrounded by a section represented by a predetermined subframe to which a synchronization signal is mapped in the time direction and a section to which the synchronization signal is mapped in the frequency direction Receiving a UE-specific reference signal mapped to resource elements that are continuous in the time direction among the reference signals;
Receiving a signal of a physical downlink shared channel using the received UE-specific reference signal;
A signal receiving method comprising:

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